1. Field of the Invention
This invention relates to an angle adjustable handle for a hand tool, more particularly to an angle adjustable handle having first and second shanks swivelable to each other between normal and angle-adjusted positions.
2. Description of the Related Art
U.S. Pat. No. 7,347,127 B2 discloses a screwdriver handle that includes a first shank and a second shank. An axial plug is formed on an end face of the first shank for pivotally engaging a groove in an end face of the second shank. A C-shaped snap fastener is disposed to retain the axial plug in the groove. Two positioning members are disposed in the first shank and are biased to engage the second shank. A control member is mounted in the second shank and is movable to urge the positioning member so as to permit the first shank to be rotatable relative to the second shank between an in-line state and an angle-adjusted state.
Another screwdriver handle, such as those disclosed in U.S. Pat. Nos. 7,434,496 B2 and 6,405,620 B2, has a similar construction except for structure and operation of the positioning member and the control member.
However, the axial plug and the snap fastener are liable to wear and break after long-time twisting operation between the first and second shanks, which renders the whole second shank unfit for long-life serviceable and usable.